DDR4 SDRAM Memory Micron DDR4 (Double Data Rate 4) SDRAM is a high-speed dynamic random-access memory internally configured as an 8-bank DRAM for the x16 configuration and as a 16-bank DRAM for the x4 and x8 configurations. These high-density devices enable system designers to take advantage of more available memory with the same number of placements, which can help to increase the bandwidth or supported feature set of a system. DDR4 memory can also enable designers to maintain the same density with fewer placements, which helps to reduce costs.